1. Field of the Invention
The present invention relates to a disc changer. Particularly, the invention relates to a disc changer incorporated in a disc drive unit, the disc changer incorporating plural discs in an accommodation section and being capable of exchanging an accommodated disc with an external disc. The disc changer has an improved disc pushing device that pushes a disc; accommodated in the accommodation section, from the disc changer to a disc discharge position.
2. Description of the Related Art
Conventionally, a cassette tape has been the mainstream medium recorded with music to provide music in a motor vehicle. However, a disc medium such as a compact disc (CD) and a mini disc (MD) is now mainly used in place of the cassette tape. Because the disc medium is thinner than the cassette tape and, particularly, because an optical disc like the CD is not in a case, a disc changer that accommodates plural discs in a reproducing unit and reproduces the recorded content by exchanging the discs is popular. A disc changer is also being developed for a digital versatile disc (DVD) type of optical disc.
This disc changer for optical discs has a disc accommodation section capable of separately accommodating plural discs, one by one, inside a casing. A swing arm takes out a desired one of the discs from this disc accommodation section, and reproduces the content of the disc using an optical head. When the reproduction ends, the swing arm returns the disc to the disc accommodation section. In general, a turntable on which a disc is rotated and a clamper that fixes the disc onto the turntable are provided at the front end of the swing arm. An optical head moves in a radial direction of the optical disk, on a moving path formed on the swing arm, on the disc that rotates on the turntable, thereby reproducing the information recorded on the disc. Generally, the disc changer has the disc accommodation section movably arranged, in the up and down directions, to facilitate the taking out of a desired disc from the disc accommodation section.
An early CD disc changer mounted on a motor vehicle was large in size, and was accommodated in a trunk of the motor vehicle. However, due to the increasingly compact size of the disc changer in recent years, the disc drive unit that incorporates the disc changer can be accommodated in a center console of an instrument panel of the motor vehicle.
The compact disc changer can accommodate plural discs in an accommodation section provided inside the disc drive unit, and can selectively reproduce the content of a desired one of the discs. The disc changer can also discharge each one of the discs to the outside of the disc drive unit, and exchange the disc with other disc. The disc changer can exchange a disc during the reproduction of the content of other disc.
Therefore, the disc changer has a disc discharge device that discharges a disc accommodated in the disc accommodation section to the outside of the disc drive unit. This disc discharge device generally has a pushing member that pushes a disc from the disc accommodation section to the disc discharge position, and a carrying mechanism that discharges the disc from the discharge position to the outside of the disc drive unit. The disc pushing member generally includes a turning lever that turns around a rotation axis to push out the disc. The carrying mechanism generally includes a roller that functions to send a disc to the inside of the disc drive unit when the disc is inserted into the disc drive unit. This roller is called a discharge roller.
However, as a result of the small disc changer in the disc drive unit, parts within the disc changer have little margin in size. Therefore, when the turning lever is used as a pushing member to push a disc from the disc accommodation section to the disc discharge position, there are problems that the turning lever collides against or is brought into contact with the disc accommodation section, with a result that the pushing member does not touch the disc and cannot push out the disc, because the height of the disc cannot match the height of the turning lever due to a variation in the size of parts. To overcome this difficulty, there is an attempt to provide a taper in the turning lever (or the accommodation member), taking into account the variation of the height of the parts in advance, and the turning lever is moved up and down, thereby absorbing a gap of heights. However, when the front end of the turning lever enters the gap of the accommodation section, the tapered turning lever often cannot absorb the height variation. When a root part of the turning lever near the rotation axis is to be brought into contact with the disc, a curvature of the turning lever becomes large, and the lever has a large length in a disc discharge direction. Consequently, the large lever cannot be accommodated in the disc drive unit.